Physics question/riddle. This is a good one, read it. - Page 47

RiggerFJ80 · 05-30-08, 05:57 PM

Quote:

Originally Posted by ed97fzj80

In what way is an airplane's forward impetus connected to the ground?

You have to move the plane forward to put wind over the wing for it to achieve lift. You really don't need wheels, but sliding along on the plane's belly might cause the occupants distress!

whodat · 05-30-08, 06:02 PM

wait just a second....Yooper, White Shark, Janice, Beerman, Phat Max, MoJ, beaufart and others voted NO to begin with also. I am in good company.

RiggerFJ80 · 05-30-08, 06:13 PM

If a plane can take off while rolling down a treadmill, why can't I fly a kite while running on one? I can make a kite achieve lift by running down the street. Why isn't this the same darn thing?

I'm not an idiot. I'm not dense. I have an IQ 0f 140. I scored an 85 the first time I took the ASVAB. It's kind of like the parents who raise the kid telling him he's dumb. Please hug me and tell me I'm not dumb...

Plowboy · 05-30-08, 06:15 PM

What I am wondering about this wheel spinning, lift, and opposite converoyer thing is: If the plane is already in the air and the wheel is not spinning, is the plane moving forward? What about pontoon (sp?) those water float things on a plane or skies, since there are no wheels, how can the plane take off?

Kavik · 05-30-08, 06:20 PM

Quote:

Originally Posted by Kavik

Someone mentioned a Sea plane, no wheels...

You are standing on the bank of a fast moving river, say 72 mph. Zero wind conditions. You have a speed radar gun in your hand.

Scenario A) Plane takes off going downstream. Lift off at 72 mph(according to radar gun).

Scenario B) Plane takes off going upstream. Lift off at 72 mph(according to radar gun).

Air speed 72mph

Going downstream hull speed 0 mph

Going upstream hull speed 144 mph

The prop thrust is totally independent of the surface of the runway.

FYI - the original riddle never mentioned the plane stay stationary. It will move. It will have air moving over the wings. It will have lift. It will fly.

Kavik · 05-30-08, 06:23 PM

Quote:

Originally Posted by RiggerFJ80

If a plane can take off while rolling down a treadmill, why can't I fly a kite while running on one? I can make a kite achieve lift by running down the street. Why isn't this the same darn thing?

I'm not an idiot. I'm not dense. I have an IQ 0f 140. I scored an 85 the first time I took the ASVAB. It's kind of like the parents who raise the kid telling him he's dumb. Please hug me and tell me I'm not dumb...

You(source of propulsion) are connected to the ground(traction/drive), the wheels are not.

Jman · 05-30-08, 07:00 PM

Quote:

Originally Posted by RiggerFJ80

I thought we were having a little fun, not making personal attacks. Nice. Anyway, for those of you who are trying to educate me, what about this...On a runway, with a hanglider strapped to you, you begin to pedal down the runway. You should achieve lift, right? Ok, now try this. In a large enough room, say a hangar, you get on the same bike, same hanglider, but you put the bike on a set of rollers(if you don't know what these are, go to Google Image Result for http://www.bikyle.com/images/EliteParbolicRoller.jpg ) (isn't this equivelent to the treadmill going in the opposite direction?) and pedal. Are you going to achieve lift? Isn't this the same thing? And I'm not a Naval Aviator, I'm a lowly enlisted Parachute Rigger.

PR1(AW) Rob Odette

Quote:

Originally Posted by RiggerFJ80

You have to move the plane forward to put wind over the wing for it to achieve lift. You really don't need wheels, but sliding along on the plane's belly might cause the occupants distress!

Quote:

Originally Posted by RiggerFJ80

If a plane can take off while rolling down a treadmill, why can't I fly a kite while running on one? I can make a kite achieve lift by running down the street. Why isn't this the same darn thing?

I'm not an idiot. I'm not dense. I have an IQ 0f 140. I scored an 85 the first time I took the ASVAB. It's kind of like the parents who raise the kid telling him he's dumb. Please hug me and tell me I'm not dumb...

As others have said, planes use props or jet engines to push off the air behind them, they care not whether they have wheels on runways, or conveyor belts, or treadmills, etc.

I just LOVE this thread.

Flip Dog · 05-30-08, 08:52 PM

OK I'm leaning on the side of the plane gaining flight, but lets look at this from a different perspective. Say the plane and conveyor belt are stationary then as the plane accelerates the conveyor belt accelerates at a speed twice as fast as the plane is accelerating. Would the plane actually travel backwards? Let me know if I am way off.

Kavik · 05-30-08, 09:16 PM

Let's say the wheels are locked up...Assuming the plane had enough power, it would drag them along until it took off.

Let's say the wheels are spinning 10,000 rpm (equivalent of 593mph) the plane would still take flight at 100mph (or whatever it does normally)

Let's say it's on a frozen lake and the wheels somehow turned all Marty Feldman. Again, it would drag them along in the direction of the prop thrust.

Are we having fun yet?

Spook50 · 05-30-08, 09:34 PM

Quote:

Originally Posted by RiggerFJ80

I have an IQ 0f 140...

Apparently physics wasn't parts of the test.

Don't worry though. I know pilots who think the plane wouldn't fly either. Hell I didn't until we had an hours-long discussion about the topic in a basic physics class I took years ago.

scottm · 05-30-08, 10:06 PM

Quote:

Originally Posted by MoGas

In what capacity? Plane Captain? Washing planes does not count. You are an embarrassment to those of us that are Navy Veterans.

AMH2(AW) D.W. Anderson (87-94)

Quote:

Originally Posted by RiggerFJ80

I thought we were having a little fun, not making personal attacks. Nice.

Geez, I thought you Navy guys got along better than that. You know: "If you can't see land it's not gay...."

MoGas · 05-30-08, 10:38 PM

Quote:

Originally Posted by scottm

Geez, I thought you Navy guys got along better than that. You know: "If you can't see land it's not gay...."

I guess he hasn't been around here long, so I'll cut him some slack. I also forgot to place a

in my post so he could tell I'm fucking with him.

Rigger,

This may have been posted earlier, but I don't want to look it up...

If your cruiser is on a treadmill, and the wheel speed is matched so it is sitting still, let's say the speedo reads 20 mph and the truck is stationary right? Yes. If you have your winch hooked to the wall and start pulling the cruiser forward with the winch, you will move forward even though the treadmill sped up to matct the overall speed, you will still fove in the direction of the force that is independant of the wheel.

Quote:

Originally Posted by RiggerFJ80

....... I have an IQ 0f 140. I scored an 85 the first time I took the ASVAB...........

Odd, I'm only a 122 IQ and I got a 93 overall the only time I took the ASVAB........

Dave

WristPin · 05-30-08, 10:44 PM

why the fuck did i click this thread???

was i expecting some pictures of a juicy steak? nay.

TCH2FLY · 05-30-08, 11:30 PM

Ok to anybody who still thinks the plane won't take off...

It friday night I'm bored so here are some of the stupid drawings I have made to try and convince people the plane will move and therefore fly
I don't feel like explaining them...figure it out on your own

I even tried to use 4x4s on an incline belt

Oh and if you still don't get it......

scottm · 05-31-08, 02:29 PM

I got a 98 first try, but I had to for any chance of being hired directly into a pilot slot at an AFRES or ANG unit. I also got 100% on every test in flight school, but still didn't get the Top Stick award. Active duty guys needed that more than I did, to get a good slot.

The running with a kite concept would be like an airplane trying to take off with a fan in front of it blowing it back to keep it stationary. Of course, it would still take off without forward movement if the fan was blowing over the wings.

Spook50 · 06-01-08, 12:11 PM

Quote:

Originally Posted by scottm

I got a 98 first try, but I had to for any chance of being hired directly into a pilot slot at an AFRES or ANG unit. I also got 100% on every test in flight school, but still didn't get the Top Stick award. Active duty guys needed that more than I did, to get a good slot.

The running with a kite concept would be like an airplane trying to take off with a fan in front of it blowing it back to keep it stationary. Of course, it would still take off without forward movement if the fan was blowing over the wings.

That'd have to be a bigass fan

I got a 96 overall here for my ASVAB. I'm also living proof that your ASVAB score doesn't dictate how smart you are. I got that score and elected to enlist into maintenence

scottm · 06-01-08, 03:32 PM

Quote:

Originally Posted by Spook50

That'd have to be a bigass fan

I flew a 100hp Light Sport plane last weekend, I think a 100hp fan would cancel out the thrust of the prop.

yooper · 06-01-08, 05:31 PM

Quote:

Originally Posted by whodat

wait just a second....Yooper, White Shark, Janice, Beerman, Phat Max, MoJ, beaufart and others voted NO to begin with also. I am in good company.

Yeah I don't understand that.

Either someone changed the results or I must have clicked on "no" by mistake, which is almost as embarrassing...

yooper · 06-01-08, 05:33 PM

Quote:

Originally Posted by RiggerFJ80

I thought we were having a little fun, not making personal attacks. Nice. Anyway, for those of you who are trying to educate me, what about this...On a runway, with a hanglider strapped to you, you begin to pedal down the runway. You should achieve lift, right? Ok, now try this. In a large enough room, say a hangar, you get on the same bike, same hanglider, but you put the bike on a set of rollers(if you don't know what these are, go to Google Image Result for http://www.bikyle.com/images/EliteParbolicRoller.jpg ) (isn't this equivelent to the treadmill going in the opposite direction?) and pedal. Are you going to achieve lift? Isn't this the same thing? And I'm not a Naval Aviator, I'm a lowly enlisted Parachute Rigger.

PR1(AW) Rob Odette

Quote:

Originally Posted by RiggerFJ80

If a plane can take off while rolling down a treadmill, why can't I fly a kite while running on one? I can make a kite achieve lift by running down the street. Why isn't this the same darn thing?

I'm not an idiot. I'm not dense. I have an IQ 0f 140. I scored an 85 the first time I took the ASVAB. It's kind of like the parents who raise the kid telling him he's dumb. Please hug me and tell me I'm not dumb...

You can't make me make a serious answer.

No. You are wrong.

Have a nice day.

ed97fzj80 · 06-02-08, 12:56 AM

Quote:

Originally Posted by RiggerFJ80

You have to move the plane forward to put wind over the wing for it to achieve lift. You really don't need wheels, but sliding along on the plane's belly might cause the occupants distress!

You didn't answer my question, so you get a a second, more intense round of Socratic pedantry. What does an airplane push on to make itself move? How does it push on it? How does how it pushes on it connect to the ground?

LoveTractor · 06-02-08, 01:51 AM

Quote:

Originally Posted by TCH2FLY

Ok to anybody who still thinks the plane won't take off...
It friday night I'm bored so here are some of the stupid drawings I have made to try and convince people the plane will move and therefore fly
I don't feel like explaining them...figure it out on your own

I even tried to use 4x4s on an incline belt

My addition...the infamous force diagram:
IH8MUD™ Forums - View Single Post - Physics question/riddle. This is a good one, read it.

The plane flies. Documented on paper(above by MANY MANY MANY posts)

AND on Mythbusters.

Reading comprehension seems to be lacking in our school system.

View Poll Results: Will the plane take off?
yes	135	34.62%
no	237	60.77%
who gives a rats a$$, I'm on the second step of 6-4-6, leave me alone!	18	4.62%
Voters: 390. You may not vote on this poll

05-30-08, 06:13 PM	#1383
RiggerFJ80 IH8MUD Rookie Join Date: Apr 2008 Location: Under a Cruiser or on the couch. Posts: 59	If a plane can take off while rolling down a treadmill, why can't I fly a kite while running on one? I can make a kite achieve lift by running down the street. Why isn't this the same darn thing? I'm not an idiot. I'm not dense. I have an IQ 0f 140. I scored an 85 the first time I took the ASVAB. It's kind of like the parents who raise the kid telling him he's dumb. Please hug me and tell me I'm not dumb... __________________ I like my beer like I like my coffee- blacker than night, stronger than God and sweeter than love! -John Stamstad '91 FJ80 2" OME, 33" BFG ATs, other stuff. Mongoose Pro Ti road racing bike DuraAce, etc.

05-30-08, 06:15 PM	#1384
Plowboy IH8MUD Regular Join Date: Apr 2002 Location: On a hill overlooking a lake in Idaho Posts: 443	What I am wondering about this wheel spinning, lift, and opposite converoyer thing is: If the plane is already in the air and the wheel is not spinning, is the plane moving forward? What about pontoon (sp?) those water float things on a plane or skies, since there are no wheels, how can the plane take off? __________________ 78LC40, sbc 327, PuPs, Aussie Locker, 4wdisc. 1948 bradley trailer Last edited by Plowboy; 05-30-08 at 06:22 PM.

05-30-08, 09:16 PM	#1389
Kavik IH8MUD Addict Join Date: Sep 2004 Location: Phoenix Posts: 731	Let's say the wheels are locked up...Assuming the plane had enough power, it would drag them along until it took off. Let's say the wheels are spinning 10,000 rpm (equivalent of 593mph) the plane would still take flight at 100mph (or whatever it does normally) Let's say it's on a frozen lake and the wheels somehow turned all Marty Feldman. Again, it would drag them along in the direction of the prop thrust. Are we having fun yet? __________________ 85' FJ60 - 2F, desmog, 4-spd, 4.88's, Aussie rear, SOA, 37's on 2" bs Copper State Cruisers #71 KavikOffRoad.com 60 Series porn

05-30-08, 11:30 PM	#1394
TCH2FLY your comments here Join Date: Aug 2005 Location: HIghlands Ranch CO TLCA# 17750 Posts: 208	Ok to anybody who still thinks the plane won't take off... It friday night I'm bored so here are some of the stupid drawings I have made to try and convince people the plane will move and therefore fly I don't feel like explaining them...figure it out on your own I even tried to use 4x4s on an incline belt Oh and if you still don't get it...... __________________ Mike W. Rising Sun (Ghost Rider division), TLCA 1994 FJZ80- ARB Locked w/4:88s, OME 850 "J"/1.5 spacer front /864 rears, 315/75-16 Cooper STTs, ARB 12K Warn, Dual Batteries, Slee Sliders, Slee Rear bumper CDL/Pin-7 etc....... My ROTW The only real damage multiplier is mounted between the driver's ears!

05-30-08, 08:52 PM	#1388
Flip Dog IH8MUD Junior Join Date: Oct 2006 Location: Bay Area Posts: 130	OK I'm leaning on the side of the plane gaining flight, but lets look at this from a different perspective. Say the plane and conveyor belt are stationary then as the plane accelerates the conveyor belt accelerates at a speed twice as fast as the plane is accelerating. Would the plane actually travel backwards? Let me know if I am way off.

05-31-08, 02:29 PM	#1395
scottm IH8MUD Lifer Join Date: Mar 2003 Location: Holland, Michigan Posts: 1,455	I got a 98 first try, but I had to for any chance of being hired directly into a pilot slot at an AFRES or ANG unit. I also got 100% on every test in flight school, but still didn't get the Top Stick award. Active duty guys needed that more than I did, to get a good slot. The running with a kite concept would be like an airplane trying to take off with a fan in front of it blowing it back to keep it stationary. Of course, it would still take off without forward movement if the fan was blowing over the wings. __________________ '03 UZJ100: wife's ride; '97 FZJ80: Traded in; '97 FZJ80 40th: Totalled; Heep: Trail Rated; '06 Specialized Epic Comp Disk: Daily Driver "if thou would have peace, be thou then prepared for war".